Re: Back & Forth - Co-routines

dxf <dxforth@gmail.com> wrote:

 
Does anyone have a reference/details for this anywhere as I can't seem to
find anything?
 

Sufficient BACK TRACKING code can be found in the following document;
I don't have a link and I won't post the code because of copyright
mark. The discussion is in Russian but the code summary is (simple) Forth.
The paper is about abstract iterator:
  AMONG <??????> EACH <????????> ITERATE
but BACK TRACKING is part of the implementation and its code is shown in
summary.
The Cyrillic here is KOI8-R


        ?????????? ???????????? ???????? ? ??????? (???????????)
                             ?.?.?????????

      ?????-????????????? ???????? ??????????? ? ????????????? ???
             199178, ?????-?????????, 14-? ????? ?.?., ?.39
                        ?-mail: mlg@iias.spb.su

... Skip abstract in Russian ...

               Enhancing the capabilities of backtracking
                             M.L.Gassanenko

Abstract:
The technique of backtracking enables one to create abstract iterator
modules, which are very convenient, but there's a severe restriction on
the use of backtracking in the body of loops controlled by these
iterators. This paper introduces a loop-like control structure that
eliminates these restrictions. A backtrackable procedure is used in it
as an iterator that controls repeating execution of a backtrackable
body; control is transferred to the iterator when the loop body succeeds
(and not when it fails). Compatibility with cut statements and
employment in rapid prototyping are discussed. A Forth implementation is
presented.

--
me